Objectives

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• Objectives
• List scientists who contributed to the cell
  theory
• List the components of the cell theory
• Compare prokaryote and eukaryote cells
• Label a plant and an animal cell
• Know the functions of cell organelles

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Early Contributions

• Robert Hooke - First person to see cells, he was
  looking at cork and noted that he saw "a great
  many boxes. (1665)
• Anton van Leeuwenhoek - Observed living cells in
  pond water, which he called "animalcules" (1673)

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• Theodore Schwann - zoologist who observed tissues
  of animals had cells (1839)
• Mattias Schleiden - botanist, observed tissues of
  plants contained cells ( 1845)
• Rudolf Virchow - also reported that every living
  thing is made of up vital units, known as cells.
  He predicted that cells come from other cells.
  (1850 )

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The Cell Theory

• 1. Every living organism is made of one or more
  cells.
• 2. The cell is the basic unit of structure and
  function. It is the smallest unit that can
  perform life functions.
• 3. All cells arise from pre-existing cells.

Why is the Cell Theory called a Theory and not a
Fact?
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Cell Features

• ALL cell have these parts
• Ribosomes make protein for use by the organism
• Cytoplasm fluid material within  cell
• DNA genetic material
• Cytoskeleton internal framework of cell
• Cell Membrane outer boundary, some things can
  cross the cell membrane

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Comprehension Checkpoint

• Answer true or false
• Robert Hooke was the first person to see cells.
• Bacteria cells have a cell membrane.
• The Cell Theory was developed by a single
  scientist.
• Plant cells have cytoplasm.
• Cells taken from fungi do not have DNA.
• Cells can only come from pre-existing cells.
• It only took five years to develop the Cell
  Theory.

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Prokaryote Cells

• The first cells to inhabit the earth
• Simple cells
• Bacteria
• These cells do NOT have a nucleus, their DNA is
  circular and floats in the cytoplasm

Some bacteria have a tail-like structure called a
flagella, that helps it to move.
A capsule surrounds some bacteria and helps them
avoid the bodys immune system
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Bacteria Images
Bacteria that causes Anthrax
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Eukaryotic Cells

• Cells found in plants, animals, protists, and
  fungi
•  
• The cell is composed of 4 main parts
• Cell membrane
• Cytoplasm
• Nucleus control center of cell, houses DNA
• Organelles small structures that carry out
  specific functions (little organs)

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Nucleus

• Usually found at center of cell
• Has a nuclear membrane nuclear pores
•  Contains cells DNA in one of 2 forms
• chromatin - DNA bound to protein (non-dividing
  cell)
• chromosomes - condesed structures seen in
  dividing cell
•  Also contains an organelle called nucleolus - whi
  ch makes the cells ribosomes

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Cell Organelles
Mitochondria this is the cells energy center.
It turns food into a chemical energy called
ATP The mitochondria is sometimes called the
powerhouse of the cell
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Cell Organelles
Golgi Apparatus processes, packages and
secretes proteins. It is comparable to a factory
or a post office.
A vesicle forms with Golgi to transport
substances outside cell.  
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Cell Organelles
Lysosome Contains digestive enzymes, breaks
things down, "suicide sac
Endoplasmic Reticulum Transport, "intracellular
highway".  -Rough ER contains many ribosomes
is involves in protein synthesis  -Smooth ER
ribosomes not found on surface
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Cytoskeleton Helps cell maintain support
shape movement a. microtubules-hollow
structures also help build cilia and
flagella b.  microfilaments-threadlike c. 
centrioles-only in animal cells used during cell
division (paired) 
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Vacuole storage area for water and other
substaces, plant cells usually have a large
central vacuole
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Protein Production

• The cell is like a factory. Its product is
  protein which goes to body to serve different
  functions.
• DNA has instructions to build protein
• These instructions are sent to ribosomes
• The ribosomes build protein and send it
  through ER
• The proteins are delivered to golgi where they
  are completed and tagged for export outside cell

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THE ANIMAL CELL
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Cheek Cells Seen Through Microscope
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Plant Cells

• Have additional structures
• CELL WALL surrounds membrane  provides
  additional support
• CHLOROPLASTS contain green pigment, function in
  photosynthesis
• CENTRAL VACUOLE large water container in center
  of cell

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PLANT CELL
Can you identify the parts?
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Anacharis Cells Viewed With a Microscope
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Animal Cell vs Plant Cell 
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Organelles With DNA

• Mitochondria and chloroplasts have their own DNA
  (separate from the nucleus)
• This supports the ENDOSYMBIOSIS THEORY
• which states that eukaryotic cells evolved
  when prokaryote cells engulfed or absorbed
  other cells.

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CELL MEMBRANE

• Selectively permeable it regulates what comes
  into the cell and what leaves the cell
• It is composed of a double layer of phospholipids
  with proteins embedded throughout